Automatic cut-off switch for radio receiving sets



Patented Dec. 1, 1925-.l

UNITED STATES assaut' PATENT oFEiJcE.

FREDERICK G. MITCHELL, OF RIDGEFIELD PARK, vNEW JERSEY.

AUTOMATIC CUT-CFF 'swIToII Foa :RADIO RECEIVING snTs.

Application ijle-d December 6, 1924. Serial No. 754,350.

predetermined time, thereby preventing un-- necessa using up of the tubes 'andbatteries when t e operator forgets to open the switch in time.

Another object' of -my improvement is to enable the operator to use my cut oit' switch also for disconnecting the circuit by hand at any desired moment.

A further object of my improvement' is to have my automatic cut off switch simple, durable and inexpensive. p

Other objects and advantagesof my improvement will hereinafter appear.

I attain these objects by the automatic out oli switch, one form of which is illustrated in the drawings or by any mechanical equivalent or obvious modification of the same.

In the drawings Fig. 1 is a section on the line 1 1 of Fig. 2, and showing sundry parts in elevation.

Fig. 2, is va view partly in section on the A line 2 2 of Fig. 1, omitting the clockwork 'handwheeh the mechanism and casing thereof.

Fig. 3 is a part elevation showing the ipointer and the dial of my automatic cut o switch, which are hereinafter more fully described. Similar numerals refer to similar parts throughout the several views.

11, 12 and 13 designate respectively the rear wall, front wall and side walls of a clockwork casing; 14 is the clock spring, which is connected to the arbor 15 and pin v16, which is connected at the`ends thereof to the walls 11- and 12 of the said casing.

'The arbor 15 and gear spindles l17,18 and 19 arepivotally connected to the said walls 11 and 12, and they have mounted thereon a train of gears 21, 22, 23, 24,

and 26, which are more or less diagrammatically shown in Fig. 1. v

20 is an escapement or s eed( regulatingY .Y mechanism, which w1th sai train oflgears and spring 14 forms the clockwork mecha.-

nism for actuating my automatic cut oi `The' front v"will "12 'f'ithe lofckwoikfV casing may be secured to the rear of the switch casing A27, whichl is shown as having at the left side thereof a metal plate 28, for mounting thereon the binding'post 30,-and at vthe right side thereofafplate of insulating 'rna-' tei-iai 29, which may be secured thereto 'in any suitable manner, for mounting thereon the binding post 31; suitable wires or conduits 51 and 52 connect 'the binding .posts the to the electrical circuit, preferably o battery A, of the radio set.

The frontwall 32 of the said switch cas ing may be connected tothe rear .of the panel 33 of the radio set.

The forward endof the spring arbor l5 yextends linto the switch casing 27, as shown in Fig. 1, and it has connected thereto-the `disc 34, which. has secured ther'eto at the periphery thereof the radial pin 38. y

A switch disc is detachably engaged by the arbor disc 34 by means of av rear' 4wardly extending pin1 39, which is secured to said switch disc 35 'at right angles theret-o, which pin is normally in contactwith the pin 38, as shown, and is caused b said pin 38 to turn the disc 35 in a clockwise diy rection, thereby forming a one way clutch. The disc 35 is carried bya yoke 36, which has two pins 37 extending rearwardly thereof into suitable openings'in the front'of said disc 35.

y The yoke 36 is securedto a spindle 45,

which passes through the front Wall 32 'of the casing 27 and the panel 33 and is pivotally mounted therein. v i' The forward end of the s indle 4bv has has thereon the hub 47, and it may vbe notched or knurled on the periphery thereof.

A dial 49, having thereon division lines orinsignia 50, is secured to the front of the panel 33, and an index or pointer 48 is carried by the hub 47 of the wheel 46, to indcate on said dial 49 the time as determined' by said clockwork.

The switch disc trical connection with the binding by means of the plate sprin 41, w ich is connected at the outer end t ereof to Said 35 is normally in elecconnected thereto the hand w eel 46, which ost 31 4 binding post 31, as shown, and terminates at the inner end thereof in the spur v44, Which is normally in sliding contact with the periphery of the disc 35, thereby completing `the electrical circuit of the radio set.

To brealcsaid circuit I provide in the periphery of the disc a depression 42,

which has thereon a linerg43 of insulating f material; when, during the rotation of the disc 35, the depression 42 in the periphery thereof is brought opposite the spur 44 on-v to rotate after the circuit is broken I pro? vide the bracket 40, which may be secured to the wall 12, to intercept the pin 39 of the disc 35 at about the saine time as the circuit is disconnected, as hereinbefore described, or shortlyy thereafter.

To set the automatic cut off switch for disconnecting the circuit at any required time, the hand wheel 46 is turned counterclockwise, thereby causing the pin 39 on the disc 35 to engage the pin 38 on the disc 34,

thereby turning the latter also counterclockwise and thereby winding up the clock spring 14; theindex or pointer 48 is then placed opposite any required division line 50 on the dial 49.

To work m for disconnecting the circuit at any desired moment, the handwheel 46 may be turned hand in a clockwise direction until the hand 48 on the dial 49 will indicate that the spur 44 of the springI 41 is in the depression 42, as above described.

Many changes may be made in the details of my automatic cut od switch for .radio receiving sets without departing from the main scope of my invention, and parts lof my inventionl may be used without other parts, if desired.v

I do not, therefore, restrict myself to the details as shown in the drawings; but I intend'to include also all mechanical equivalents and reasonablyobvious modiiications of the same Within the scope of my inven` tion.

rgets tol automatic switch by hand,-

What I claim as my invention and desire to secure by Letters Patent is:

' 1. In an automatic cut oi` switch for an electric circuit of a radio receiving set a clockwork mechanism, a spring arbor therein, a driving member connected to said arbor, to rotate therewith, an engaging pin projecting from said member, a driven memv.

2. In an automatic cnt o' switch for an e electric circuit of a radio receiving set a clockwork mechanism,'a spring arbor therein, a driving member secured tov said arbor,

to rotate therewith, an engaging means carried by said member, a driven member carrying a corresponding means to beimpelled by said engaging means, and forminoP therewith a one way clutch, to turn said5 driven member in one direction and to .allow said driven member to be turned in the saine direction independently of said arbor, an electrical conductor in sliding contact with said to be turned in the same direction independently of said arbor, an electrical conductor in contact with said driven disc, thereby completing said circuit, and a means on said driven disc for automatically separating said conductor therefrom, thereby breaking said circuita FREDERICK G. MITCHELL.

driven member, thereby completing said ciif' 

